The Harvard Brain Tissue Resource Center is a national resource for the acquisition, processing, storage and distribution of postmortem (PM) brain specimens from normal controls (CON), as well as individuals with a variety of movement disorders (Huntington's chorea and Parkinson's disease), dementia (Alzheimer's disease) and major psychoses (schizophrenia and bipolar disorder). For the past 20 years, the HBTRC has been distributing tissue specimens to neuroanatomists, neuropathologists, neuropharmacologists, neurochemists and molecular biologists. In so doing, this facility has acted as a "seed" for more than 150 scientific publications, most having appeared in distinguished refereed journals. In the past 1.5 years, the HBTRC has undergone a major re-structuring that has resulted in an increase in the overall quality and efficiency of its operation. An important outcome of this re-organization has been an increase in the overall number of fresh cases acquired and a marked decrease in the length of the postmortem interval (PMI). As a result of this effort, abundant tissue suitable for a broad array of state-of-the-art research applications can now be provided to the neuroscience community. Since the number of CONs received in the past year has also been increased by 50 percent and is projected to increase by as much as 100 percent over the next year, the HBTRC is now able to match CONs for age, PMI and gender with respect to a variety of brain disordered groups. For the major psychoses, where the acquisition of PM brains is extremely difficult, the number of cases has also been increased by 50 percent in the past 1.5 years. Since these are largely from community-based referrals, the potential confounding effects of institutionalization, inanition and substance abuse will be reduced in studies of the psychiatric disorders. The HBTRC has established a website with information for potential donors and their families, pathologists involved in brain removal, as well as investigators seeking tissue for their research; all necessary forms can now be downloaded from the "Net." Most recently, the HBTRC has been developing a user-interactive database for the Internet so that investigators who receive tissue from the "bank" can obtain demographics, neuropathology reports and images of gross dissections and histological slides for their cases. Over the next five years, all of these changes will enhance the "brain bank" in its role as a vital national resource.